Depending on the condition the current asking prices for 1985 Chevy Silverado 1500's are going for between $1,200 to $6,000. Most appraisal websites like Kelly Blue Book & Edmunds do not offer values on vehicles that are older than 1990 due to the variables that are taken into account on used vehicles. You might want to take it into your local Chevrolet dealer for an accurate appraisal.
The value of your 1985 Chevy Silverado is contingent on many variables. The amount of mileage the truck has on it and how well it has been maintained, are two of the major considerations when estimating it's value. A vehicle of this type is worth around $800.00 as a trade in on another vehicle or maybe as high as $1500.00 in a private sell if it is in excellent condition.